This disclosure relates generally to solenoids of the type utilized in vehicle starter motors. More specifically, this disclosure relates to solenoids including an integrated ignition magnetic switch.
Vehicle starter motors are typically provided with a drive assembly and a solenoid, with a shift lever connecting the solenoid to the drive assembly. When a solenoid coil is energized, a solenoid plunger extends, thereby actuating the shift lever and engaging a starter pinion gear with a flywheel of the engine. Vehicle starter motors that utilize a soft-start engagement system must provide a substantial amount of current prior to actual crank to begin rotation of the starter pinion gear and to cause the pinion gear to engage with the flywheel. The current needed typically ranges from 200 A to 400 A depending on the particular starter motor and engine. This amount of current is much greater than the 4-6 A that common ignition switches are capable of reliably handling. Therefore a separate ignition magnetic switch (IMS) is utilized, limiting current draw of the starter motor upon activation of the IMS to current in the rage of 2-4 A. When the IMS is activated, a pull-in coil in the solenoid is connected to a vehicle battery. Current then flows to the starter motor allowing the pinion gear to rotate and engage the flywheel. The IMS is a separate component from the solenoid and starter motor and is located external to these components.